Paper Details

Research on composite members is popular as they have major role in high rise buildings and bridges withaesthetically pleasing complex designs. In this study, steel encased composite beams are considered in which structuralsteel I section is embedded within the reinforced concrete. A non linear structural analysis of encased composite beamsincorporating the material non linearity and geometric non linearity is conducted to evaluate the flexural behavior andtorsional behavior of composite beams. The primary goal of the research is to conduct an analytical investigation onfully encased composite beams with various I section of similar cross section area under flexure and torsion. Unlikeother steel encased composite beams, in this study, the longitudinal reinforcement bars are completely excluded.Therefore, behavior and failure mode of beams are greatly affected by the steel beam core. ie. even in the absence oflongitudinal bars, the steel section can provide the flexural strength for the beam. This research is focused on thecomparison of flexural–torsional behavior of steel-encased composite members with conventional reinforced beamsusing five set of I section namely ISHB 150, ISMB 225, ISWB 200, ISLB 250 and ISHB 200. The load-deflection behavioris plotted. From the above studies, ISHB 200 has shown a better performance under flexure. Moreover, the depth ofsection is reduced compared to conventional reinforced beams. In this way the dead load of the structure is beenreduced. But the reduction of depth is limited by incorporating the flexural rigidity of the section. The torsional actionson beams are studied with ISHB 200 using lateral stirrups of various spacing. Maximum shear strength is attained withlower spacing of lateral stirrups. Application of frictional surface on the top and bottom flanges of I sections to avoid theslippage of concrete from steel suface showed a positive effects on the structure.

Chinnu Sabu, Dr. Alice Mathai, “ANALYTICAL INVESTIGATION OF ENCASED COMPOSITE BEAMS UNDER FLEXURE AND TORSION”, International Journal of Advance Engineering and Research Development (IJAERD), Vol. 5, Issue 4, pp. 1999-2011, April 2018.